#include<stdio.h>
#include<stdlib.h>

typedef char BTDataType;

typedef struct BinaryTreeNode
{
	BTDataType data;
	struct BinaryTreeNode* leftNode;
	struct BinaryTreeNode* rightNode;

}BtNode;

BtNode* BuyNode(BTDataType x);

void preorder(BtNode* root);
void inorder(BtNode* root);
void postorder(BtNode* root);